We preprocess the data by dividing \(T\) -second clips into \(T\)  non-overlapping parts (\(T=30\)  for Kinetics-700 [1]} and \(T=10\)  for AudioSet [2]}) and sampling 16 frames from each. For audio stream, we take waveform sampled at 44.1 kHz and convert it to log-mel-scaled spectrogram. We augment audio data with random frequency/time masking using SpecAugment [3]}, and visual data with color normalization, random resizing, random horizontal flip, and random cropping to obtain \(112 \times 112\)  pixel frames; for test data, we resize videos to 128 pixels on the shorter side and take three equidistant crops of \(128 \times 128\)  pixels to cover the entire region. We also apply audio-visual synchronized temporal jittering [4]}.
